If someone barges into an discussion like that and you attempt to confront them with reason and argumentation, you're gonna have a bad time only further poisoning your perspective of the "other side".
And sure, this sort of thing is not unique to climate change denial. What is unique is the consequences that denial is having to the planet (and therefore me), and their presence in forums that are otherwise at least vaguely aligned with facts.
tl;dr: People may deny the problem, but when the solution isn't political in the first place, I can't see why it matters.
Yes, renewables are getting quite cheap, and coal is dying one way or another. But the amount of coal that gets pumped into the atmosphere before we're done with it will be far higher than it needed to be.
If you think the solution isn't political, then obviously you'll disagree with me, but you're unlikely to convince me that government intervention doesn't matter here.
But when you already have a solution in mind... Politics is an obstacle or a gauntlet, not the solution you're working towards.
Some combination of: they're related to me, they vote, they barge into conversations and start arguing against the facts.